The present invention relates to a method for preparation of meso-meso, xcex2xe2x80x94xcex2, xcex2xe2x80x94xcex2, triply linked porphyrin arrays, represented by general formula 1, by oxidizing the corresponding meso-meso linked Zn(II) porphyrins, represented by general formula 2, with a selected combination of Lewis acid and quinone oxidant, and a method for preparation of meso-meso; xcex2xe2x80x94xcex2, xcex2xe2x80x94xcex2, triply porphyrin tetramers (general formula 1, n=2) from Zn(II) porphyrin monomers, represented by general formula 3 where R1-R9 are substituted and especially R2, R5, and R8 are aryl groups, and R10, R11, and R12 are unsubstituted. The meso-meso, xcex2xe2x80x94xcex2, xcex2xe2x80x94xcex2, triply linked Zn(II) porphyrin arrays exhibit remarkable planarity and exceptionally large electronic interactions as evidenced by their absorption and electronic properties.
Porphyrins exhibit strong absorbance in the visible region, strong fluorescence and phosphorescence, and high electric conductivity, because the HOMO-LUMO gap is relatively small. Furthermore, porphyrins have an advantage to accommodate almost all metal ions in their cavities as a ligand and such metallations and peripheral substitutions enable the tuning of optical and electrochemical properties, thus providing a variety of compounds that can fulfill the required properties when used in functional materials and devices. In nature, porphyrins are responsible for various important functions in biological processes such as oxidation-reduction reactions in metabolism, photosynthesis, and respiration. With these backgrounds, prophyrin-based molecular systems such as energy-converting functional materials and bio-mimetic catalysts have been actively developed. Recently, considerable attention has been paid to multi-porphyrin systems from a viewpoint of their application as opto-electronic material. In this line, syntheses of porphyrin polymers or oligomers bearing long, rigid, planar, and thus the exploration of extensively xcfx80-conjugated electronic systems and new devices based on the strong absorbance in the visible region, strong fluorescence and phosphorescence, and small optical HOMO-LUMO energy gap have been actively attempted.
Among these, the present inventor has reported the synthesis of directly meso-meso linked linear porphyrin polymers (consisting of 300-400 porphyrin subuints) and discrete meso-meso linked porphyrin oligomers up to a 128 mer. In addition, he also proposed the possibility of the synthesis of fused porphyrin oligomers by linking two xcex2- and xcex2-positions directly through oxidation of meso-meso linked porphyrin arrays.
The linear meso-meso linked porphyrin arrays have been regarded to be a promising unit for the usage as optical wire and electric molecular wire in light of rod-like structure, large electronic interactions between the neighboring porphyrin that are sufficient to induce rapid non-coherent excitation energy transfer hopping, and lack of an energy sink that blocks the energy transfer cascade long the array. These properties are apparently induced from the directly linked and perpendicular conformation of the neighboring porphyrins. The perpendicular conformation, however, leads to the disruption of xcfx80-conjugation and therefore the electric conductivity of the meso-meso linked porphyrins is only modest. When the perpendicular meso-meso linked porphyrin arrays are converted into flat and coplanar arrays by linking twoxcex2xe2x80x94xcex2, xcex2xe2x80x94xcex2 bonds, we may reach to extensively xcfx80-conductive porphyrin arrays that will be very promising as a molecular wire in a realistic molecular scale.
The present inventor proposed the linearly fused porphyrin arrays bearing meso-xcex2 and meso-xcex2 double linkages as a more practical candidate for molecular wire. But such arrays are not sufficient for practical applications as optical wire and molecular wire in terms of the electronic interaction and molecular size.
Therefore, the present inventor proposed a new method of preparation of meso-meso, xcex2xe2x80x94xcex2, xcex2xe2x80x94xcex2 triply directly linked porphyrin arrays that extend linearly to form a tape-shape porphyrin tape (JP2000-110157 application: JP Laid Open Pub. 2001-294591). However, this synthetic protocol was only applied to the preparation of the porphyrin tapes in which the number of the porphyrin was very limited, due to concurrent peripheral xcex2-halogenations.
The object of the present invention is to explore porphrin-based more extensively xcfx80-conjugated network which realized much longer molecular length and more electron delocalization, hence providing conjugated porphyrin arrays that will be used as optical wire and electric conducting wire.
For the use as electric wire, it is desirable to minimize the HOMO-LUMO gap as small as possible. For this purpose, extensively conjugated porphyrin arrays consisting of many porphyrins are required. Accordingly, the second object of the present invention is to establish the effective method for synthesis of conjugated porphyrin arrays of very small HOMO-LUMO gap.
In the course of these studies, the present inventor have found that a new synthetic method for converting meso-meso linked meso,meso"" phenyl capped Zn(II) porphyrin oligomers to meso-meso, xcex2xe2x80x94xcex2, xcex2xe2x80x94xcex2 triply directly linked Zn(II) porphyrin oligomers with quinone oxidant in the presence of suitable Lewis acid in refluxing toluene or benzonitrile solution.
The first one of the present invention is meso-meso, xcex2xe2x80x94xcex2,xcex2xe2x80x94xcex2 triply directly linked, so-called fused porphyrin oligomers represented by general formula 1. 
(wherein, R1-R24 are respectively selected independently from the group consisting of hydrogen, halogen, hydroxyl group, mercapto group, amino group, nitro group, cyano group, carboxyl group, sulfonic acid group, substituted or non-substituted alkyl group, substituted or non-substituted aryl group, substituted or non-substituted alkoxy group, substituted or non-substituted aryloxy group, substituted or non-substituted alkylthio group, substituted or non-substituted arylthio group, alkylamino group, substituted or non-substituted arylamino group, substituted or non-substituted carboxylate group, substituted or non-substituted carboxylic acid amino group, substituted or non-substituted sulfonate group, substituted or non-substituted sulfonamide group, substituted or non-substituted carbonyl group, substituted or non-substituted silyl group or substituted or non-substituted siloxy group, n is an integer bigger than 2, M is 2H or a complex replaced two hydrogen atoms of porphyrin ring with metal atom selected from the group of metal atoms of A,. wherein metal atom group A is Zn, Mg, Ca, Sr, Ba, Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Ti, Zr, Hf, V, Nb, Ta, Th, U, Cr, Mo, W, Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Cd, Hg, Al, Ga, In, Ti, Si, Ge, Sn, Pb, As, Sb, and Bi.)
Desirably, the present invention is the above mentioned fused porphyrin oligomers, wherein in the above mentioned general formula 1, R1, R4, R10, R13, R16, R22 are selected independently from phenyl groups having substituent selected independently from alkyl group or alkoxy group of carbon number 1 or more, R7 and R19 are respectively selected independently from the group consisting of hydrogen, halogen, hydroxyl group, mercapto group, amino group, nitro group, cyano group, carboxyl group, sulfonic acid group, substituted or non-substituted alkyl group, substituted or non-substituted aryl group, substituted or non-substituted alkoxy group, substituted or non-substituted aryloxy group, substituted or non-substituted alkylthio group, substituted or non-substituted arylthio group, alkylamino group, substituted or non-substituted arylamino group, substituted or non-substituted carboxylate group, substituted or non-substituted carboxylic acid amino group, substituted or non-substituted sulfonate group, substituted or non-substituted sulfonamide group, substituted or non-substituted carbonyl group, substituted or non-substituted silyl group or substituted or non-substituted siloxy group.
More desirably, the present invention is the bove mentioned fused porphyrin oligomers, wherein in the above mentioned general formula 1, R1, R4, R10, R13, R16, R22 are the compound independently selected from the group consisting of 3,5-di-tertialbutylphenyl group or 3,5-di-octyloxyphenyl group.
The second one of the present invention is the method for synthesis of the fused Zn(II) porphyrin oligomres (n=0, or an integer bigger than 1 and M is Zn in above mentioned general formula 1 featuring the neighboring porphyrin rings are meso-meso, xcex2xe2x80x94xcex2, xcex2xe2x80x94xcex2, triply directly linked in a linear fashion from the meso-meso linked zn(II)-porphyrin oligomers represented by general formula 2, and the corresponding fused porphyrin free base oligomers (Mxe2x95x902H)) repared by demetalization of the above fused Zn(II) porphyrin oligomers, or the fused M(+m)-porphyrin oligomers by inserting other metal instead of Zn (wherein, M is a metal selected from above mentioned group of metal atoms except Zn, m is a possible ionic valence number of each metal), represented by general formula 1. 
In the general formula 2, R1-R24 are same as to general formula 1, n is 0 or integer bigger than 1. In this synthetic method, the conversion from the meso-meso linked porphyrin oligomers to the fused porphyrin oligomers was carried out in solvent with quinone oxidants in the presence of suitable Lewis acid containing rare earth ion.
Desirably, the second one of the present invention is the method for synthesis of the fused Zn(Ii) porphyrin oligomers wherein R1, R4, R7, R10, R13, R16, R19 and R22 of the above mentioned general formula 1 are the phenyl group or the phenyl group substituted with substituents selected independently from alkyl group or alkoxy group of carbon number 1 or more, and is the method for synthesis of the fused porphyrin free base oligomers wherein M is 2H by demetallation of the said fused Zn(II) porphyrin oligomers, and the fused M(+m) porphyrin oligomers by inserting other metal instead of Zn (wherein, M is a metal selected from the above mentioned group of metal atoms except Zn, m is a possible ionic valence number of each metal). In this synthetic method, the conversion from the mesa-mesa linked porphyrin oligomers to the fused porphyrin oligomers was carried out in solvent with quinone oxidants in the presence of suitable Lewis acid containing rare earth ion.
The third one of the presefit invention is the method for synthesis of the mesa-mesa, xcex2xe2x80x94xcex2, xcex2xe2x80x94xcex2 directly triply linked, so-called fused zn(II) porphyrin dimers, and their corresponding fused free base porphyrin dimers prepared by demetalization of the above fused Zn(II) porphyrin dimer, and the fused M(+m) porphyrin compound (wherein, M is a metal selected from above mentioned group of metal atoms except Zn, m is a possible ionic valence number of each metal), which are prepared by oxidative dimerization of a Zn(II) porphyrin monomer represented by general formula 3 
(wherein M is Zn, R10-R12 are hydrogen and R1-R9 are respectively selected independently from the group consisting of hydrogen, halogen, hydroxyl group, mercapto group, amino group, nitro group, cyano group, carboxyl. group, sulfonic acid group, substituted or non-substituted alkyl group, substituted or non-substituted aryl group, substituted or non-substituted alkoxy group, substituted or non-substituted aryloxy group, substituted or non-substituted alkylthio group, substituted or non-substituted arylthio group, alkylamino group, substituted or non-substituted arylamino group, substituted or non-substituted carboxylate group, substituted or non-substituted carboxylic acid amino group, substituted or non-substituted sulfonate group, substituted or non-substituted sulfonamide group, substituted or non-substituted carbonyl group, substituted or non-substituted silyl group or substituted or non-substituted siloxy group). The oxidative dimerization reaction is carried out in solvent with quinone oxidants in the presence of suitable Lewis acid containing rare earth ion.
Desirably, the third one of the present invention is the method for synthesis of the meso-meso, xcex2xe2x80x94xcex2, xcex2xe2x80x94xcex2 directly triply linked, so-called fused Zn(II) porphyrin dimers, and the fused metal free porphyrin dimers prepared by demetalization of the above Zn(II)-porphyrin dimers, and the fused M(+m) porphyrin compound (wherein, M is a metal selected from above mentioned group of metal atoms except Zn, m is a possible ionic valency number of each metal) represented by general formula 3, wherein, R1, R3, R4, R6, R7, R9-R12 are hydrogen, R2, R5 and R 8 of above mentioned general formula 3 are the phenyl group having substituent selected independently from alkyl group or alkoxy group of carbon number 1 or more.
More desirably, the third one of the present invention is the method for synthesis of the above mentioned fused Zn(II) porphyrin dimers, the above mentioned fused metal free porphyrin dimers prepared by demetalization of the above Zn(II)-porphyrin dimers, and the above mentioned fused M(+m)-porphyrin compound (wherein, M is a metal selected from above mentioned group of metal atoms except Zn, m is a possible ionic valence number of each metal), wherein the phenyl group having substituent selected independently from alkyl group or alkoxy group of carbon number 1 or more is the phenyl group whose 3, 5 positions are substituted by tertiary butyl group or octyloxy group, even more desirably, the third one of the present invention is the method for synthesis of the above mentioned fused metal free porphyrin dimers prepared by demetallation of the above fused Zn(II) porphyrin dimers and the corresponding fused M(+m) porphyrin compound (wherein, M is a metal selected from above mentioned group of metal atoms except Zn, m is a possible ionic valence number of each metal). The oxidative dimerization reaction is carried out under refluxing condition in aromatic hydrocarbon solvents in the presence of quinone oxidants selected from quinones and Lewis acids containing rare earth lanthanide element.